1. Multiple-choice question: This topic is entitled *** 12, with 5 points for each question and 60 points for each question. Only one of the four options given in each small question meets the requirements of the topic.
1. If {x|x2
≤a, a ∈R}, then the value range of a is ()
A. Functions with a period of π
C, () f x is an even function d with a period of 2π, and () f x is a function with a period of π, with the range of [0, 1].
1 1. In the plane rectangular coordinate system, if there are two different points, (b a A), (B A B- in the function) (x f y = on the image,
Then it is called, (B A is a function) (x f y = a set of symmetrical points about the y axis.
(